Abstract

The median time from CLL diagnosis to development of Richter's transformation varies, but has been estimated to be between 2-5 years. This is in contrast to the prevailing notion that Richter's transformation is a late event in CLL. There are several known risk factors for development of the transformation in a CLL patient. These include clinical factors such as bulky lymphadenopathy (>5cm) and advanced Rai stage (Rai III-IV), and biological characteristics such as unmutated immunoglobulin heavy chain (IGHV) genes; positive expression of CD38, CD49d, and ZAP-70; and stereotyped B-cell receptors. CLL patients who have high-risk genetic features such as del17p13 or del11q23 (by FISH) are also at a higher risk of developing Richter's transformation.